Organic glass screen printing resolution screen printing screen printing machine are briefly introduced
A type of resolution, organic glass screen printing
In image processing of scanning input and print output, using several different resolution.Resolution refers to the unit length, the pattern that can record the distinguished point, line, the maximum number of parallel lines/mm.
Often use the resolution of the general has four kinds:
1, the scanning resolution Spi (samples/inch) : resolution.Is used scanners, digital cameras.
2, PPi display resolution (pixels per inch) : is a graphic display number, the number of phase element.
3, print resolution Dpi (word/inch) : the resolution of the printer output.
4, printed copy image resolution LPi (line number per inch) : image replication and line number, line frequency, the resolution of the halftone.The resolution of the common use Dpi instead of Spi, PPi.
Second, the kinds of organic glass screen printing resolution
(a), the scanning resolution (resolution) input:
Scanner gray-scale resolution, generally in the directions are given.Refers to the per inch (cm) on the original image through the scanner for the amount of information.It by scanner has the maximum optical resolution or interpolated resolution limit.
Said: 1, the optical resolution is the scanner itself of the optical system to attain the highest input resolution (also known as the physical resolution).It is divided into vertical and horizontal resolution, is refers to the scanner (CCD) real resolution.
(1) horizontal resolution: the resolution of the optical system, CCD real, also called optical resolution.Such as 300-600 dpi, 300-1200 dpi, 1000-2000 dpi, high retaining time of up to 4000-8000 dpi.
(2) vertical Dpi resolution refers to the scanner, and stepping motor in the mechanical design of mobile and decide how many steps per inch, it related to the mechanical transmission parts.Vertical resolution is less important than the horizontal resolution.
2, the maximum resolution (interpolation resolution) : refers to the optical resolution scanning, through the software interpolation method to calculate the resolution of the scanner's largest.Is generally higher than the optical resolution is 2-4 times.This resolution can't keep impressing image quality.
3, image resolution: refers to the amount of information, image storage to general image pixels to the horizontal and vertical direction (the amount of Pi (ei).Such as resolution 640-480, says there are about 640 pixel image horizontally.There are 480 pixels in the vertical direction.The value the more pixels, the greater the image clearer.Some people think that the higher image resolution, the better is wrong, although reasonable, but not practical.Because the human eye is a certain distance of the recognition ability to don't see the nuances of the image.Is like an image with 600 dpi and 1000 dpi resolution printing at the same time, the result is the same quality.So the resolution is set too much is not necessary, due to the increased amount of information is a waste of time.But resolution and not too small, otherwise the level losses, image restoration.
4, the display resolution: a computer screen can show the total amount of information at a time.Refers to the horizontal points per inch on display, commonly used display screen has 14 ", 15 ", 17 ", 19 ".There are three kinds of display resolution 640 x 640 x 800, 640, 800 by 600, the large screen display of high resolution.The size of the display resolution, will only affect the end user to use images to work convenience, does not affect the quality of the output of the image data.
(2) the output resolution:
Output resolution: only for printer output and printing operations, it said the file sent to image setter or printer need pixels per inch (Ppi) or Dpi.Copying method, and network agreement, the resolution of the output devices such as integrated set, determine the exact output image resolution.
Printer resolution: used to measure output devices in the horizontal and vertical direction, and can produce points per inch.The higher the resolution of the printer (laser phototypesetter), the network is fine, image tone more continuity.The resolution of the printer limits the printer can reproduce the maximum number of single colors.
Three, the relationship between input and output resolution
1, the input resolution: relationship between Dpi and Lpi Dpi > Lpi and a half times
Input (scanning resolution) and the relationship between the output resolution (resolution)
Input line resolution = record number (Lpi output image maximum length (inches)/input image maximum length x 2 (inches)
Scanning resolution is to add the number of network cable twice, such as scanning is set to 80 line/inches of manuscript 150-200 dpi.
2, the output resolution: Dpi > Lpi ten to twenty times
Phototypesetter output to grayscale value is proportional to the phototypesetter resolution Dpi and add screen density is inversely proportional to the Lpi.
Grayscale = output resolution Dpi (2 + 1)/images plus cable for Lpi
Such as scanning electric points above 10 * 10, 16 * 16 pixels (electric extension 23 * 23 scanning a node).Such as phototypesetter output film, the original line number is 50-100 line/inch, should be set on the phototypesetter 1200 dpi.
As the output image grayscale request for 256 - bit, so to 150 line/inch screen density, recorder (scanner) the output of the above should be set to 2500 dpi resolution.
Four, organic glass screen printing resolution formula conversion
The best image resolution = = N * 2 x plus screen density scanning resolution image best resolution (N for zoom ratio) color original scan resolution = add line number x 2 x magnification example: the original size 2 x magnification, and line number is 150 dpi, set the scanning resolution should be = 2 x 2 x 150 = 600 dpi.